Rose of Heaven.—­See “Viscaria Coeli Rosa.”

Rose of Sharon.—­See “Hibiscus Syriacus.”

Rubus.—­See “Blackberries.”

Rudbeckia (Cone Flower.)—­Hardy annuals yielding yellow flowers in July.  They are readily grown from seed sown early in spring, and will grow in any garden soil, but naturally succeed best in deeply-worked, well-manured ground.  They may be increased by division in October or November, as well as in spring-time.  Height, 3 ft.

Ruscus Aculeatus (Butchers Broom).—­A hardy evergreen shrub which thrives in any rich soil, and may be increased by division of the root.  Height, 1 ft.

Ruta Graveolens.—­This hardy evergreen shrub is a species of Rue.  It enjoys a good, rich soil, in which it flowers freely in August.  Cuttings may be struck under a hand-glass.  Height, 3 ft.

Ruta Patavina (Rue of Padua).—­For rock-work this hardy perennial is very useful.  It likes a dry yet rich and light soil.  At midsummer it produces an abundance of greenish-yellow flowers.  It can be raised from seed, or cuttings may be struck under a hand-glass.  Height, 6 in.

S

Saffron, Spring.—­See “Bulbocodium.”

Sage.—­This useful herb likes a rich, light soil, and is propagated by division of the root, by cuttings, or by seed.

Saintpaulia Ionantha.—­The leaves of this plant spread themselves laterally just over the soil, forming a rosette, in the centre of which spring up large violet-like flowers.  It is a continuous bloomer.  A rather light, rich soil or vegetable mould suits it best.  The seed, which is very minute, should be sown early in spring, in gentle heat:  to prevent it being washed away, the pots may stand up to the rims in water for a while when the ground wants moisture.  Height, 1 ft.

St. John’s Wort.—­See “Hypericum.”

Salix Reticulata.—­A dwarf creeping plant whose dark green leaves eminently fit it for the rock-work or carpet bedding.  It will grow in any soil, but prefers a moist one, and produces unattractive brown flowers in September.  Propagated in spring by detaching rooted portions from the parent plant and planting them in moist, sandy loam.  Height, 2 in.

Salpiglossis.—­Very beautiful half-hardy annuals which are greatly prized for cut bloom.  A light but not over-rich soil suits them best.  The seed may be sown in the open border early in spring, or preferably on a hotbed at the same period.  For early flowering raise the plants in the autumn, and winter them in a frame or greenhouse.  Flowers are produced in July and August.  Height, 2 ft.

Salsafy (Vegetable Oyster).—­Sow the seed in any good garden soil—­deep sandy loam is best—­towards the end of April in drills 1 ft. apart, and thin the plants out to a distance of 6 in. from each other.  The roots may remain in the ground till required for use, or be lifted in October and stored in the same way as Beet or Carrots.  They are prepared for table in the same manner as Parsnips, and are also used for flavouring soups.